METHOD OF PROVIDING OPTIMAL FIELD PROGRAMMING OF ELECTRONIC FUSES

Description

FIELD OF THE DISCLOSURE

[0001] The present disclosure generally relates to the field of electronic fuses. In particular, the present disclosure is directed to a method and design structure for providing optimal field programming of electronic fuses.

BACKGROUND

[0002] Electronic fuses may commonly be found in many integrated circuit designs. One exemplary electronic fuse is a poly silicon fuse link that is coupled to a voltage line (usually referred to as FSource) at one end, and to an n-channel field-effect transistor (NFET), which is usually referred to as a programming FET, at its opposite end. During a fuse programming operation, a voltage is supplied by the FSource and the programming FET is turned on for a certain duration of time, which allows controlled electromigration to occur. The controlled electromigration causes a salicide/boron pile-up on an anode side of the poly fuse link. As a result, the resistance across the poly fuse link may rise from hundreds of ohms to many Kilo-ohms, in effect opening or "programming" the electronic fuse.

[0003] As is known in the art, the rise in fuse resistance during a fuse programming operation must meet a particular integrated circuit chip characteristic requirement. Using a "one size fits all" approach to a fuse programming operation may have two undesirable results: (1) a ruptured fuse or (2) a weakly programmed fuse. As such, if chip characteristics vary, the fuse programming process may need to be altered in order to provide the desired fuse yield. That is, the environmental variables of a fuse programming process, e.g., programming Vdd, FSource voltage, or the fuse programming duration, may need to be varied on a chip-by-chip basis according to a different characteristic requirement of each chip. Integrated circuit chip manufacturers have satisfactorily determined on a chip-by-chip basis whether and how one or more environmental variables need to be altered. As a result, the proper fuse programming conditions may be applied by automated test equipment during the normal manufacturing test flow and, thus, the electronic fuse programming operation is successfully performed.

[0004] While the conditions and parameters that are related to the electronic fuse programming process, which includes the environmental variables of a fuse programming process, are known to integrated circuit chip manufacturers, they are not known to customers that are receiving the chip, as it is not the manufacturer's practice to supply this information to customers. However, customers may wish to program electronic fuses in the field for a wide variety of reasons and, thus, customers may benefit from knowledge of the electronic fuse programming process. For example, upon receiving a chip of the customer's specifications from the manufacturer, a customer may wish to program electronic fuses in order to implement functional or performance settings therein. Unfortunately, without the proper electronic fuse programming information that takes into account the environmental variables of the customer's chip specifically, programming electronic fuses in the field (i.e., outside the manufacturing test environment) will likely result in low fuse yield.

[0005] Integrated circuit chip manufacturers have utilized an electronic chip identification (ECID) macro of a chip which may be used for storing non-test related data (e.g., chip identification data, such as lot number, wafer ID, chip coordinates). Chip customers may access this chip identification information. However, integrated circuit chip manufacturers have not provided customers in any fashion the knowledge to extend manufacturing processes (e.g., effectively program electronic fuses) to the field.

[0006] A need exists for a method of providing optimal field programming of electronic fuses, in order to enable chip customers to perform an electronic fuse programming process in the field that produces a desired fuse yield.

SUMMARY OF THE DISCLOSURE

[0007] The invention is defined in claims 1 and 9.

[0008] In one embodiment, a method of programming an electronic fuse of a chip in the field by a customer of the manufacturer of the chip is provided. The method includes determining one or more optimal fuse programming conditions for one or more electronic fuses of a chip; storing an indicator of the one or more optimal fuse programming conditions in one or more memory bits on the chip; providing the chip to a customer in the field; and instructing the customer to access the one or more optimal fuse programming conditions from the one or more memory bits to enable the customer to program at least one of the one or more electronic fuses.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] For the purpose of illustrating the invention, the drawings show aspects of one or more embodiments of the invention. However, it should be understood that the present invention is not limited to the precise arrangements and instrumentalities shown in the drawings, wherein:

FIG. 1 illustrates a functional block diagram of one example of an integrated circuit chip, upon which is stored a fuse programming condition identifier for enabling a method of programming an electronic fuse in the field;

FIG. 2 illustrates a flow diagram of one example of a method of programming an electronic fuse by use of the fuse programming condition identifier that is stored on the integrated circuit chip;

FIG. 3 illustrates a flow diagram of one example of a method of determining one or more optimal fuse programming condition identifiers for enabling a method of programming an electronic fuse in the field;

FIG. 4 illustrates a flow diagram of one example of a method of programming an electronic fuse in the field by an integrated circuit chip customer; and

FIG. 5 is a block diagram of a design flow process using the design structure according to an embodiment.

DETAILED DESCRIPTION

[0010] In one embodiment, the present disclosure includes a method of providing optimal fuse programming conditions by which an integrated circuit (IC) chip customer may program electronic fuses in the field, i.e., outside of the manufacturing test environment. In particular, an optimal fuse programming identifier, which is correlated to a set of optimal fuse programming conditions, is provided to the customer in readable fashion on the customer's IC chip. After accessing the optimal fuse programming identifier on the customer's IC chip, the customer may apply a fuse programming process in the field according to the correlated optimal fuse programming conditions. In one example, this may allow the customer to achieve a desired electronic fuse yield.

[0011] FIG. 1 illustrates a functional block diagram of an exemplary IC chip 100, upon which is stored a fuse programming condition identifier for enabling a method of programming an electronic fuse in the field. IC chip 100 may be any integrated circuit chip, such as an application specific integrated circuit (ASIC) device, that includes at least one arrangement of electronic fuses (eFUSEs). For example, FIG. 1 shows that IC chip 100 includes a first eFUSE bank 110 and a second eFUSE bank 112, which may each be a single eFUSE or a string of eFUSEs (e.g., forming a certain logic macro within IC chip 100). The eFUSEs of banks 110 and/or 112 may be initially in an unprogrammed (i.e., closed) state. In one example, first eFUSE bank 110 and/or eFUSE bank 112 may be eFUSEs that form certain redundancy structures, such as structures commonly found in memory arrays (i.e., redundant wordlines or redundant columns). In this example, the eFUSEs may be programmed to disconnect a normal wordline and replace it with a redundant wordline when, for example, the normal wordline is detected as defective. In another example, first eFUSE bank 110 and/or second eFUSE bank 112 may be eFUSEs that form an ECID macro, which contains eFUSEs that are programmed to a value that reflects, for example, chip identification data.

[0012] Additionally, FIG. 1 shows a detail of an exemplary eFUSE 114 of first eFUSE bank 110. More specifically, eFUSE 114 may be a poly silicon fuse link that is coupled to a voltage line (FSource) at one end, and to an NFET, which is referred to as a programming FET 116, at its opposite end. The gate of programming FET 116 is controlled by the chip voltage (Vdd) of IC chip 100. During an eFUSE programming operation, a voltage is supplied by the FSource and programming FET 116 is turned on for a certain duration of time by applying Vdd, which allows controlled electromigration to occur. The controlled electromigration may cause a salicide/boron pile-up on an anode side of the eFUSE 114. As a result, the resistance across eFUSE 114 may rise (e.g., from hundreds of ohms to many Kilo-ohms), in effect opening (i.e., programming) eFUSE 114.

[0013] Referring again to FIG. 1, IC chip 100 further includes a storage device 118, within which is stored a digital value that is related to one or more fuse programming condition identifiers 120. Storage device 118 may be any mechanism by which one or more bits of digital data may be stored, such as, but not limited to, a memory device or one or more eFUSEs. In one example, storage device 118 may be a non-volatile static random access memory (SRAM) device or a non-volatile programmable read-only memory (PROM) device. In another example, storage device 118 may be one or more surplus eFUSEs within a bank of existing eFUSEs within IC chip 100, such as, but not limited to, surplus eFUSEs 114 within first eFUSE bank 110 or second eFUSE bank 112. In yet another example, storage device 118 may be, or may be part of, one or more eFUSEs of an ECID. One or more fuse programming condition identifiers may be represented by one or more logical values stored in a storage device, such as storage device 118. For example, a programmed or unprogrammed state of an eFUSE 114 may represent a logic one (1) or zero (0), e.g., unprogrammed eFUSE=1, programmed eFUSE=0, or visa versa.

[0014] Those skilled in the art will recognize that an integrated circuit device, which is represented by IC chip 100, may include arrangements of one or more logic functions, which for simplicity are not shown in FIG. 1.

[0015] The conditions of an eFUSE programming process may be controlled precisely on a chip-by-chip basis during the manufacturing test operation in order to achieve a high eFUSE yield, by avoiding ruptured eFUSEs or weakly programmed eFUSEs. The optimal eFUSE programming conditions are variable on a chip-by-chip basis due to manufacturing process variations, e.g., from one IC chip 100 to a next IC chip 100, to a next IC chip 100, and so on. One exemplary method of determining the optimal eFUSE programming conditions is described in US Patent No 7,170,299 "Electronic fuse blow mimic and methods for adjusting electronic fuse blow," which is incorporated herein by reference in its entirety. The '299 patent describes a system, method, and program product for adjusting an environmental variable of a fuse programming of an electronic fuse. In particular, a mimic NFET may be coupled to a fuse programming source voltage line, a fuse programming gate voltage line, and a chip ground in the same manner as the electronic fuse, except that the mimic NFET is not attached to an electronic fuse. The on-current (I-ON) and off-current (I-OFF) of the mimic NFET are measured to determine a fuse programming current (1-PROGRAM) of the electronic fuse. The environmental variable is adjusted based on the determined programming current. Another example of a method is summarized with reference to a method 300 of FIG. 3 below.

[0016] Example environmental variables include, but are not limited to, FSource, Vdd, background leakage current, I-PROGRAM, chip vs. tester ground offset, programming duration, temperature, and accuracy of test equipment. Fuse programming condition identifier 120 may be a digital code of one or more bits that may be correlated to a certain eFUSE programming condition, which may be a unique optimal eFUSE programming condition for a given IC chip 100. For example, fuse programming condition identifier 120 may be uniquely encoded with a first value on a first IC chip 100 for correlating to a first optimal eFUSE programming condition therefor, uniquely encoded with a next unique value on a next IC chip 100 for correlating to a next optimal eFUSE programming condition therefor, and uniquely encoded with a next unique value on a next IC chip 100 for correlating to a next optimal eFUSE programming condition therefor. The code contained in fuse programming condition identifier 120 may correlate to one or any combination of multiple environmental variables, which include, for example, FSource, Vdd, background leakage current, I-PROGRAM, chip vs. tester ground offset, programming duration, temperature, and accuracy of test equipment.

[0017] The number of bits that form fuse programming condition identifier 120 is dependent on the number of or combinations of environmental variables needed to convey the optimal eFUSE programming conditions for a given IC chip. In one example, fuse programming condition identifier 120 may be a 1-bit code that correlates to a first and second optimal Vdd value, e.g., fuse programming condition identifier 120=0 for Vdd=1.20 volts and fuse programming condition identifier 120=1 for Vdd=1.35 volts. In another example, fuse programming condition identifier 120 may be a 2-bit code that correlates to up to four optimal Vdd values, e.g., fuse programming condition identifier 120=00 for Vdd=1.20 volts, fuse programming condition identifier 120=01 for Vdd=1.35 volts, and fuse programming condition identifier 120=10 for Vdd=1.50 volts. In yet another example, fuse programming condition identifier 120 may be an n-bit binary code that correlates to the actual digital value (having a certain resolution) of a certain eFUSE programming condition, e.g., an 8-bit, 10-bit, 12-bit, or 16-bit binary word that represents the actual value of, for example, FSource, Vdd, or 1-PROGRAM. In all cases, the information of fuse programming condition identifier 120 may be stored by the chip manufacturer during the normal manufacturing test flow. In the case wherein the bits forming fuse programming condition identifier 120 are memory bits, these bits are set to a desired state via known memory write operations. Alternatively, in the case wherein the bits forming fuse programming condition identifier 120 are eFUSEs 114, one or more eFUSEs 114 are set to either a programmed or unprogrammed state according to a desired code.

[0018] As exemplified by IC chip 100 of FIG. 1, the chip manufacturer may provide a fuse programming condition identifier, such as fuse programming condition identifier 120, within a chip and, thereby, provides a readable mechanism that is accessible by a customer and by which a customer may then correlate an optimal eFUSE programming condition for his/her chip. Correlation may occur in a variety of ways. In one example, a correlation may include comparison of a fuse programming condition identifier with a digitally stored value (e.g., in a lookup data table). In another example, a correlation may include comparison of a fuse programming condition identifier with a printed manual. In yet another example, a correlation may include reading the fuse programming condition identifier to reveal an actual programming condition. As a result, the fuse programming condition identifier may enable a customer to apply an optimal eFUSE programming condition, which is unique to a particular chip, in order to efficiently program eFUSEs in the field, i.e., outside of the manufacturing test environment, such as during the customer's card level test operation. More details are provided with reference to FIGS. 2, 3, and 4.

[0019] FIG. 2 illustrates a flow diagram of one embodiment of a method 200 of programming an electronic fuse by use of a fuse programming condition identifier, such as fuse programming condition identifier 120, which is stored on an integrated circuit chip, such as IC chip 100. Method 200 includes, but is not limited to, the following steps.

[0020] At step 210, a fuse programming condition identifier that is stored in one or more memory bits on a chip are accessed. In one example and referring again to FIG. 1, after delivering a chip, such as IC chip 100, from the chip manufacturer to the chip purchaser, fuse programming condition identifier 120 of storage device 118 is accessed by the chip purchaser. In the case wherein the bits forming fuse programming condition identifier 120 are memory bits, these bits are accessed via known memory read operations. Alternatively, in the case wherein the bits forming fuse programming condition identifier 120 are eFUSEs 114, the programmed or unprogrammed state of the one or more eFUSEs 114 is detected via standard circuitry that is associated with, for example, first eFUSE bank 110 or second eFUSE bank 112.

[0021] At step 212, one or more optimal eFUSE programming conditions are correlated with the information of fuse programming condition identifier, such as correlated with the information of fuse programming condition identifier 120 of storage device 118 of IC chip 100. In one example, this correlation may be performed by the chip manufacturer providing the chip purchaser any standard method of correlating each possible value that may be encoded in fuse programming condition identifier 120 with an optimal eFUSE programming condition e.g., a software lookup table, an electronic or printed guidebook, or a telephone customer service center. In one example, a 1-bit fuse programming condition identifier 120 that is set to "0" may correlate to, for example, set Vdd=1.20 volts and that is set to "1" may correlate to, for example, set Vdd=1.35 volts. In another example, a 2-bit fuse programming condition identifier 120 that is set to "00" may correlate to, for example, set Vdd=1.20 volts; that is set to "01" may correlate to, for example, set Vdd=1.35 volts; and that is set to "10" may correlate to, for example, set Vdd=1.50 volts.

[0022] At step 214, one or more fuses on the IC chip are programmed utilizing the one or more correlated eFUSE programming conditions. In particular, the IC chip purchaser applies the correlated optimal eFUSE programming conditions that were extracted from his/her IC chip during, for example, manufacturing wafer and/or module test operations, in order to program one or more IC chip purchaser-selected eFUSEs 114.

[0023] FIG. 3 illustrates a flow diagram of one embodiment of a method 300 of determining one or more optimal fuse programming condition identifiers for enabling a method of programming an electronic fuse, such as programming an electronic fuse by use of method 300. In one example, one or more optimal fuse programming condition identifiers may be determined by use of method 300 on a chip-by-chip basis during a manufacturing test operation. Method 300 includes, but is not limited to, the following steps.

[0024] At step 310, a plurality of IC test chips are tested for the optimal chip programming conditions. In particular, a chip manufacturer executes an eFUSE programming process on a plurality (e.g., hundreds to millions) of IC test chips, in order to understand the preferred way to program the eFUSEs for a selection of environmental variations.

[0025] At step 312, a plurality of test values of a correlating parameter are determined from the plurality of IC test chips. A correlating parameter may be any measurable value that may indicate a corresponding value for a fuse programming environmental condition. For example, a fuse programming current may be measured at a particular fuse programming condition value, e.g., a particular Vdd value. Each of the plurality of test values may be for one of a plurality of fuse programming condition sets. The test values are based upon the eFUSE-programming information that is gathered in step 310 for every known process variation. For example, physical measurements of an IC test chip may be mapped to certain eFUSE-programming parameters.

[0026] At step 314, each IC test chip is tested for an actual value of the correlating parameter. In one example and referring to paragraphs 0018 through 0020 of the co-pending ' 120 patent application, the background leakage current (I-BKG) of the IC chip under test is measured, the on-current (I-ON) of a mimic programming FET at nominal Vdd and FSource values is measured, I-BKG is subtracted from I-ON in order to determine the fuse programming current (I-PROGRAM).

[0027] At step 316, an optimal one of the plurality of fuse programming condition sets is determined for the IC chip under test by comparing an actual value to a plurality of test values. In one example and referring to paragraph 0021 of the co-pending ' 120 patent application, a three-way decision may be performed. Specifically, an upper level threshold, for example, 14mA, and a lower level threshold, for example, 10mA, are set for the determined I-PROGRAM. If the determined I-PROGRAM is higher than the upper level threshold, here 14mA, the programming Vdd may be decreased, for example, from the preset 1.35V to 1.20V. If the determined I-PROGRAM is lower than the lower level threshold, here 10mA, the programming Vdd may be increased, for example, from the preset 1.35V to 1.50V. Also, if the determined I-PROGRAM is within the range between the upper level threshold, here 14mA, and the lower level threshold, here 10mA, the programming Vdd may be considered proper and be maintained the same as the preset value, here 1.35V. In doing so, an optimal value of the programming Vdd is determined that correlates to the actual I-PROGRAM of the IC chip under test.

[0028] At step 318, an indicator of the optimal one of the plurality of fuse programming condition sets is stored as the fuse programming condition identifier. For example, if the optimal programming Vdd is 1.20V, a 2-bit fuse programming condition identifier 120 for the IC chip under test may be set to "00;" if the optimal programming Vdd is 1.35V, the 2-bit fuse programming condition identifier 120 may be set to "01;" and if the optimal programming Vdd is 1.50V, the 2-bit fuse programming condition identifier 120 may be set to "10."

[0029] FIG. 4 illustrates a flow diagram of a method 400 of programming an electronic fuse in the field by, for example, an integrated circuit chip customer. Method 400 includes, but is not limited to, the following steps.

[0030] At step 410, one or more optimal fuse programming conditions are determined. These conditions will apply to all eFUSEs on a given chip such as IC chip 100 by, for example, performing steps 310 through 316 of method 300 of FIG. 3.

[0031] At step 412, during the manufacturing test operation, an indicator of the one or more optimal fuse programming conditions is stored in one or more memory bits on the IC chip under test. For example, an indicator of the one or more optimal fuse programming conditions is stored in fuse programming condition identifier 120 of storage device 118 of IC chip 100, as described, for example, in FIG. 1 and in step 318 of method 300 of FIG. 3.

[0032] At step 414, the chip manufacturer provides an IC chip, such as IC chip 100, to a customer in the field.

[0033] At step 416, the IC chip customer is instructed on how to access the one or more optimal fuse programming conditions from the one or more memory bits in order to enable the customer to program at least one of the one or more eFUSEs. For example, the IC chip manufacturer may provide instructions to the IC chip customer on how to access, for example, fuse programming condition identifier 120 of storage device 118 of IC chip 100. Additionally, the IC chip manufacturer may provide the chip purchaser a standard method of correlating each possible value that may be encoded in fuse programming condition identifier 120 with a respective optimal eFUSE programming condition. Standard correlation methods include, but are not limited to, a software lookup table, an electronic or printed guidebook, or calling by telephone a customer service center.

[0034] FIG. 5 shows a block diagram of an example design flow 500. Design flow 500 may vary depending on the type of IC being designed. For example, a design flow 500 for building an application specific IC (ASIC) may differ from a design flow 500 for designing a standard component. Design structure 520 is preferably an input to a design process 510 and may come from an IP provider, a core developer, or other design company or may be generated by the operator of the design flow, or from other sources. Design structure 520 comprises IC chip 100 in the form of schematics or HDL, a hardware-description language (e.g., Verilog, VHDL, C, etc.). Design structure 520 may be contained on one or more machine readable medium. For example, design structure 520 may be a text file or a graphical representation of IC chip 100. Design process 510 preferably synthesizes (or translates) IC chip 100 into a netlist 580, where netlist 580 is, for example, a list of wires, transistors, logic gates, control circuits, I/O, models, etc. that describes the connections to other elements and circuits in an integrated circuit design and recorded on at least one of machine readable medium. This may be an iterative process in which netlist 580 is resynthesized one or more times depending on design specifications and parameters for the circuit.

[0035] Design process 510 may include using a variety of inputs; for example, inputs from library elements 530 which may house a set of commonly used elements, circuits, and devices, including models, layouts, and symbolic representations, for a given manufacturing technology (e.g., different technology nodes, 32nm, 45 nm, 90 nm, etc.), design specifications 540, characterization data 550, verification data 560, design rules 570, and test data files 585 (which may include test patterns and other testing information). Design process 510 may further include, for example, standard circuit design processes such as timing analysis, verification, design rule checking, place and route operations, etc. One of ordinary skill in the art of integrated circuit design can appreciate the extent of possible electronic design automation tools and applications used in design process 510 without deviating from the scope and spirit of the invention. The design structure of the invention is not limited to any specific design flow.

[0036] Ultimately, design process 510 preferably translates IC chip 100, along with the rest of the integrated circuit design (if applicable), into a final design structure 590 (e.g., information stored in a GDS storage medium). Final design structure 590 may comprise information such as, for example, test data files, design content files, manufacturing data, layout parameters, wires, levels of metal, vias, shapes, test data, data for routing through the manufacturing line, and any other data required by a semiconductor manufacturer to produce IC chip 100. Final design structure 590 may then proceed to a stage 595 where, for example, final design structure 590: proceeds to tape-out, is released to manufacturing, is sent to another design house or is sent back to the customer.

[0037] Exemplary embodiments have been disclosed above and illustrated in the accompanying drawings. It will be understood by those skilled in the art that various changes, omissions and additions may be made to that which is specifically disclosed herein without departing from the present invention.

Claims

1. A method (300) of programming an electronic fuse of a chip (100) in the field by a customer of the manufacturer of the chip, the method characterised by comprising:

determining (316, 410) one or more optimal fuse programming conditions for one or more electronic fuses of a chip;

storing (318, 412) an indicator of said one or more optimal fuse programming conditions in one or more memory bits on said chip;

providing (414) said chip to a customer in the field; and

instructing (416) said customer to access said one or more optimal fuse programming conditions from said one or more memory bits to enable said customer to program at least one of said one or more electronic fuses.

2. A method according to claim 1, wherein said one or more memory bits are included in an electronic chip identification macro.

3. A method according to claim 1 or 2, wherein said one or more memory bits includes an electronic fuse.

4. A method according to any preceding claim, wherein said one or more optimal fuse programming conditions is determined on a chip-by-chip basis during manufacture testing of said chip.

5. A method according to claim 4, wherein said determining of said one or more optimal fuse programming conditions includes:

testing a plurality of test chips for one or more optimal chip programming conditions;

determining a plurality of test values of a correlating parameter from said plurality of test chips, each of said plurality of test values being for one of a plurality of fuse programming condition sets;

testing said chip for an actual value of said correlating parameter;

determining an optimal one of said plurality of fuse programming condition sets for said chip by comparing said actual value to said plurality of test values;

storing an indicator of said optimal one of said plurality of fuse programming condition sets as said fuse programming condition identifier.

6. A method according to claim 5, wherein said correlating parameter is a fuse programming current for said chip.

7. A method according to claim 6, wherein said fuse programming current is determined by:

measuring a background current on a fuse programming source line of an electronic fuse of said chip;

measuring an 'on' current on said fuse programming source line at a predetermined value of a chip programming parameter without exposing said electronic fuse to said 'on' current; and

determining a difference between said 'on' current and said background current.

8. A method according to any preceding claim, wherein said one or more optimal fuse programming conditions includes a condition selected from the group consisting of a fuse programming source voltage, a fuse programming gate voltage, a fuse programming time, and any combinations thereof.

9. A design structure for programming an electronic fuse of a chip, the design structure characterised by comprising:

a means for determining (316, 410) one or more optimal fuse programming conditions for one or more electronic fuses of a chip;

a means for storing (318, 412) an indicator of said one or more optimal fuse programming conditions in one or more memory bits on said chip;

a means for providing (414) said chip to a customer in the field; and

a means for instructing (416) said customer to access said one or more optimal fuse programming conditions from said one or more memory bits to enable said customer to program at least one of said one or more electronic fuses.

10. A design structure according to claim 9, , wherein said one or more memory bits are included in an electronic chip identification macro.

11. A design structure according to claim 9 or 10, wherein said one or more memory bits includes an electronic fuse.

12. A design structure according to claim 9, 10 or 11, wherein said means for determining of said one or more optimal fuse programming conditions is conducted on a chip-by-chip basis during manufacture testing of said chip.

13. A design structure according to any of claims 9 to 12, wherein said means for determining of said one or more optimal fuse programming conditions includes:

a means for testing a plurality of test chips for optimal chip programming conditions;

a means for determining a plurality of test values of a correlating parameter from said plurality of test chips, each of said plurality of test values being for one of a plurality of fuse programming condition sets;

a means for testing said chip for an actual value of said correlating parameter;

a means for determining an optimal one of said plurality of fuse programming condition sets for said chip by comparing said actual value to said plurality of test values; and

a means for storing an indicator of said optimal one of said plurality of fuse programming condition sets as said fuse programming condition identifier.

14. A design structure according to claim 13, wherein said correlating parameter is a fuse programming current for said chip.

15. A design structure according to claim 14, wherein said fuse programming current is determined by:

measuring a background current on a fuse programming source line of an electronic fuse of said chip;

measuring an 'on' current on said fuse programming source line at a predetermined value of a chip programming parameter without exposing said electronic fuse to said 'on' current; and

determining a difference between said 'on' current and said background current.

Ansprüche

1. Verfahren (300) zum Programmieren einer elektronischen Sicherung eines Chips (100) am Einsatzort durch einen Kunden des Chipherstellers, wobei das Verfahren dadurch gekennzeichnet ist, dass es Folgendes umfasst:

Festlegen (316, 410) eines oder mehrerer optimaler Sicherungsprogrammierbedingungen für eine oder mehrere elektronische Sicherungen eines Chips;

Speichern (318, 412) eines Hinweismerkers der einen oder mehreren optimalen Sicherungsprogrammierbedingungen in einem oder mehreren Speicherbits auf dem Chip;

Liefern (414) des Chips an einen Kunden am Einsatzort; und

Anleiten (416) des Kunden, wie auf die eine oder die mehreren optimalen Sicherungsprogrammierbedingungen von dem einen oder den mehreren Speicherbits zugegriffen werden kann, um den Kunden zu befähigen, von der einen oder den mehreren elektronischen Sicherungen wenigstens eine zu programmieren.

2. Verfahren nach Anspruch 1, wobei das eine oder die mehreren Speicherbits in einem elektronischen Chipidentifizierungsmakro enthalten sind.

3. Verfahren nach Anspruch 1 oder 2, wobei das eine oder die mehreren Speicherbits eine elektronische Sicherung enthalten.

4. Verfahren nach einem beliebigen vorhergehenden Anspruch, wobei die eine oder die mehreren optimalen Sicherungsprogrammierbedingungen für jeden einzelnen Chip während der Fertigungsprüfung des Chips festgelegt werden.

5. Verfahren nach Anspruch 4, wobei das Festlegen der einen oder der mehreren optimalen Sicherungsprogrammierbedingungen Folgendes beinhaltet:

Prüfen einer Vielzahl von Prüfchips nach einer oder mehreren optimalen Sicherungsprogrammierbedingungen;

Bestimmen einer Vielzahl von Prüfwerten eines korrelierenden Parameters aus der Vielzahl von Prüfchips, wobei jeder aus der Vielzahl von Prüfwerten für eine Gruppe aus einer Vielzahl von Gruppen der Sicherungsprogrammierbedingungen gilt;

Prüfen des Chips nach einem tatsächlichen Wert des korrelierenden Parameters;

Festlegen einer optimalen Gruppe aus der Vielzahl von Gruppen der Sicherungsprogrammierbedingungen für den Chip durch Vergleichen des tatsächlichen Werts mit der Vielzahl von Prüfwerten;

Speichern eines Hinweismerkers der optimalen Gruppe aus der Vielzahl von Gruppen der Sicherungsprogrammierbedingungen als die Kennung der Sicherungsprogrammierbedingungen.

6. Verfahren nach Anspruch 5, wobei es sich bei dem korrelierenden Parameter um einen Sicherungsprogrammierstrom für den Chip handelt.

7. Verfahren nach Anspruch 6, wobei der Sicherungsprogrammierstrom durch Folgendes festgelegt ist:

Messen eines Hintergrundstroms in einer Leitung der Sicherungsprogrammierquelle einer elektronischen Sicherung des Chips;

Messen eines "Ein"-Stroms in der Leitung der Sicherungsprogrammierquelle bei einem zuvor festgelegten Wert eines Chip-Programmierparameters, ohne dass die elektronische Sicherung dem "Ein"-Strom ausgesetzt wird; und

Bestimmen einer Differenz zwischen dem "Ein"-Strom und dem Hintergrundstrom.

8. Verfahren nach einem vorhergehenden Anspruch, wobei eine oder mehrere optimale Sicherungsprogrammierbedingungen eine Bedingung enthalten, die aus der Gruppe ausgewählt ist, die eine Sicherungsprogrammiersourcespannung, eine Sicherungsprogrammier-Gatespannung, einen Sicherungsprogrammierzeitpunkt und beliebige Kombinationen hiervon enthält.

9. Gestaltungsstruktur (design structure) zum Programmieren einer elektronischen Sicherung eines Chips, wobei die Gestaltungsstruktur dadurch gekennzeichnet ist, dass sie Folgendes umfasst:

Mittel zum Festlegen (316, 410) einer oder mehrerer optimaler Sicherungsprogrammierbedingungen für eine oder mehrere elektronische Sicherungen eines Chips;

Mittel zum Speichern (318, 412) eines Hinweismerkers einer oder mehrerer optimaler Sicherungsprogrammierbedingungen in einem oder mehreren Speicherbits auf dem Chip;

ein Mittel zum Liefern (414) des Chips an einen Kunden am Einsatzort; und

ein Mittel zum Anleiten (416) des Kunden, wie auf eine oder mehrere Sicherungsprogrammierbedingungen aus dem einen oder den mehreren Speicherbits zugegriffen werden kann, um den Kunden zu befähigen, von der einen oder den mehreren elektronischen Sicherungen wenigstens eine zu programmieren.

10. Gestaltungsstruktur nach Anspruch 9, wobei das eine oder die mehreren Speicherbits in einem elektronischen Chipidentifizierungsmakro enthalten sind.

11. Gestaltungsstruktur nach Anspruch 9 oder 10, wobei das eine oder die mehreren Speicherbits eine elektronische Sicherung enthalten.

12. Gestaltungsstruktur nach Anspruch 9, 10 oder 11, wobei die Mittel zum Festlegen der einen oder mehreren optimalen Sicherungsprogrammierbedingungen für jeden einzelnen Chip während der Fertigungsprüfung des Chips zum Einsatz kommen.

13. Gestaltungsstruktur nach einem der Ansprüche 9 bis 12, wobei die Mittel zum Festlegen einer oder mehrerer optimaler Sicherungsprogrammierbedingungen Folgendes enthalten:

Mittel zum Prüfen einer Vielzahl von Prüfchips nach optimalen Chip-Programmierbedingungen;

Mittel zum Festlegen einer Vielzahl von Prüfwerten eines korrelierenden Parameters aus der Vielzahl von Prüfchips, wobei jeder Prüfwert aus der Vielzahl von Prüfwerten für eine Gruppe aus einer Vielzahl von Gruppen von Sicherungsprogrammierbedingungen gilt;

Mittel zum Prüfen des Chips nach einem tatsächlichen Wert des korrelierenden Parameters;

Mittel zum Festlegen einer optimalen Gruppe aus der Vielzahl von Gruppen aus Sicherungsprogrammierbedingungen für den Chip durch Vergleichen des tatsächlichen Werts mit der Vielzahl von Prüfwerten; und

Mittel zum Speichern eines Hinweismerkers der optimalen Gruppe aus der Vielzahl von Gruppe aus Sicherungsprogrammierbedingungen als Kennung der Sicherungsprogrammierbedingung.

14. Gestaltungsstruktur nach Anspruch 13, wobei es sich bei dem korrelierenden Parameter um ein Sicherungsprogrammierstrom für den Chip handelt.

15. Gestaltungsstruktur nach Anspruch 14, wobei der Sicherungsprogrammierstrom durch Folgendes festgelegt wird:

Messen eines Hintergrundstroms in einer Sicherungsprogrammier-Sourceleitung einer elektronischen Sicherung des Chips;

Messen eines "Ein"-Stroms auf der Sicherungsprogrammier-Sourceleitung bei einem zuvor festgelegten Wert eines Chip-Programmierparameters, ohne dass die elektronische Sicherung dem "Ein"-Strom ausgesetzt wird; und

Bestimmen einer Differenz zwischen dem "Ein"-Strom und dem Hintergrundstrom.

Revendications

1. Procédé (300) de programmation d'un fusible électronique d'une puce (100) sur le terrain par un client du fabricant de la puce, le procédé étant caractérisé par le fait de comprendre les étapes consistant à :

déterminer (316, 410) une ou plusieurs conditions de programmation de fusibles optimales pour un ou plusieurs fusibles électroniques d'une puce,

mémoriser (318, 412) un indicateur desdites une ou plusieurs conditions de programmation de fusibles optimales dans un ou plusieurs bits de mémoire sur ladite puce,

fournir (414) ladite puce à un client sur le terrain, et

donner pour instruction (416) audit client d'accéder auxdites une ou plusieurs conditions de programmation de fusibles optimales à partir desdits un ou plusieurs bits de mémoire pour permettre audit client de programmer au moins l'un desdits un ou plusieurs fusibles électroniques.

2. Procédé selon la revendication 1, dans lequel lesdits un ou plusieurs bits de mémoire sont inclus dans une macro d'identification de puce électronique.

3. Procédé selon la revendication 1 ou 2, dans lequel lesdits un ou plusieurs bits de mémoire comprennent un fusible électronique.

4. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdites une ou plusieurs conditions de programmation de fusibles optimales sont déterminées sur une base puce par puce au cours d'un essai de fabrication de ladite puce.

5. Procédé selon la revendication 4, dans lequel ladite détermination desdites une ou plusieurs conditions de programmation de fusibles optimales comprend les étapes consistant à :

tester une pluralité de puces d'essai en ce qui concerne une ou plusieurs conditions de programmation de fusibles optimales,

déterminer une pluralité de valeurs d'essai d'un paramètre de corrélation à partir de ladite pluralité de puces d'essai, chaque valeur de ladite pluralité de valeurs d'essai correspondant à un ensemble d'une pluralité d'ensembles de conditions de programmation de fusibles,

tester ladite puce en ce qui concerne une valeur actuelle dudit paramètre de corrélation,

déterminer un ensemble optimal de ladite pluralité d'ensembles de conditions de programmation de fusibles pour ladite puce en comparant ladite valeur actuelle à ladite pluralité de valeurs d'essai,

mémoriser un indicateur dudit ensemble optimal de ladite pluralité d'ensembles de conditions de programmation de fusibles comme ledit identificateur de conditions de programmation de fusibles.

6. Procédé selon la revendication 5, dans lequel ledit paramètre de corrélation est un courant de programmation de fusible pour ladite puce.

7. Procédé selon la revendication 6, dans lequel ledit courant de programmation de fusible est déterminé en :

mesurant un courant de fond sur une ligne de source de programmation de fusible d'un fusible électronique de ladite puce,

mesurant un courant « actif » sur ladite ligne de source de programmation de fusible à une valeur prédéterminée d'un paramètre de programmation de puce sans exposer ledit fusible électronique audit courant « actif », et

déterminant une différence entre ledit courant « actif » et ledit courant de fond.

8. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdites une ou plusieurs conditions de programmation de fusibles optimales comprennent une condition sélectionnée à partir du groupe constitué d'une tension de source de programmation de fusible, d'une tension de grille de programmation de fusible, d'un temps de programmation de fusible, et toute combinaison de ceux-ci.

9. Structure de conception destinée à programmer un fusible électronique d'une puce, la structure de conception étant caractérisée par le fait de comprendre :

un moyen destiné à déterminer (316, 410) une ou plusieurs conditions de programmation de fusibles optimales pour un ou plusieurs fusibles électroniques d'une puce,

un moyen destiné à mémoriser (318, 412) un indicateur desdites une ou plusieurs conditions de programmation de fusibles optimales dans un ou plusieurs bits de mémoire sur ladite puce,

un moyen destiné à fournir (414) ladite puce à un client sur le terrain, et

un moyen destiné à donner pour instruction (416) audit client d'accéder auxdites une ou plusieurs conditions de programmation de fusibles optimales à partir desdits un ou plusieurs bits de mémoire pour permettre audit client de programmer au moins l'un desdits un ou plusieurs fusibles électroniques.

10. Structure de conception selon la revendication 9, dans laquelle lesdits un ou plusieurs bits de mémoire sont inclus dans une macro d'identification de puce électronique.

11. Structure de conception selon la revendication 9 ou 10, dans laquelle lesdits un ou plusieurs bits de mémoire comprennent un fusible électronique.

12. Structure de conception selon la revendication 9, 10 ou 11, dans laquelle ledit moyen de détermination desdites une ou plusieurs conditions de programmation de fusibles optimales est commandé sur une base puce par puce au cours d'un essai de fabrication de ladite puce.

13. Structure de conception selon l'une quelconque des revendications 9 à 12, dans laquelle ledit moyen de détermination desdites une ou plusieurs conditions de programmation de fusibles optimales comprend :

un moyen destiné à tester une pluralité de puces d'essai en ce qui concerne une ou plusieurs conditions de programmation de fusibles optimales,

un moyen destiné à déterminer une pluralité de valeurs d'essai d'un paramètre de corrélation à partir de ladite pluralité de puces d'essai, chaque valeur de ladite pluralité de valeurs d'essai correspondant à un ensemble d'une pluralité d'ensembles de conditions de programmation de fusibles,

un moyen destiné à tester ladite puce en ce qui concerne une valeur actuelle dudit paramètre de corrélation,

un moyen destiné à déterminer un ensemble optimal de ladite pluralité d'ensembles de conditions de programmation de fusibles pour ladite puce en comparant ladite valeur actuelle à ladite pluralité de valeurs d'essai, et

un moyen destiné à mémoriser un indicateur dudit ensemble optimal de ladite pluralité d'ensembles de conditions de programmation de fusibles comme ledit identificateur de conditions de programmation de fusibles.

14. Structure de conception selon la revendication 13, dans laquelle ledit paramètre de corrélation est un courant de programmation de fusible pour ladite puce.

15. Structure de conception selon la revendication 14, dans laquelle ledit courant de programmation de fusible est déterminé en :

mesurant un courant de fond sur une ligne de source de programmation de fusible d'un fusible électronique de ladite puce,

mesurant un courant « actif » sur ladite ligne de source de programmation de fusible à une valeur prédéterminée d'un paramètre de programmation de puce sans exposer ledit fusible électronique audit courant « actif », et

déterminant une différence entre ledit courant « actif » et ledit courant de fond.

Drawing